Battery
The battery's innovative design with slitted current collector tabs ensures reliable power extraction by allowing alternate connections, addressing welding failure issues and improving structural integrity.
Patent Information
- Application Number
- JP2021215157
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- Filing Date
- 2021-12-28
- Publication Date
- 2024-12-17
- Estimated Expiration
- 2041-12-28
AI Technical Summary
Conventional batteries face issues with structural reliability due to welding failures between current collector tabs and terminals, particularly in power generation elements, leading to power extraction problems.
The battery design includes current collector tabs with slits that divide the end portions, allowing them to be electrically connected to adjacent tabs in the thickness direction, ensuring that even if a joint fails, power can be extracted through other connections.
This design enhances structural reliability by enabling power extraction from the power generation element even if welding failures occur, maintaining electrical connectivity through alternate connections.
Smart Images

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Abstract
Description
[Technical field]
[0001] This application relates to batteries. [Background technology]
[0002] Patent Document 1 discloses a joining method for joining a laminated structure formed by stacking a plurality of metal foils and a plurality of insulating films to a metal plate placed at the end of the laminated structure, the joining method comprising: a first step of alternately stacking metal foils having notches formed at their ends and insulating films to produce a laminated structure; a second step of bringing a metal plate into contact with the end of the laminated structure where the notches are formed, and bending the ends of the metal foil in contact with the metal plate in a uniform manner in the stacking direction; and a third step of welding the ends of the metal foil to the metal plate in a state in which the ends of the metal foil in contact with the metal plate are bent in a uniform manner in the stacking direction.
[0003] According to the joining method described in Patent Document 1, the following effects can be expected. The ends of the metal foil are bent in a predetermined direction by the metal plate. Furthermore, the laser light is moved in the direction in which the ends of the metal foil are bent in a uniform manner. This promotes the extension of the ends of the metal foil in that direction due to thermal expansion. As a result, even if the ends of the metal foil try to separate from the metal plate due to the impact when the metal plate melts, the ends of the metal foil are pressed against the metal plate. As a result, gaps are unlikely to occur between the ends of the metal foil and the metal plate, and the metal foil and the metal plate can be welded with fewer welding defects and stable welding results. As a result, the welding strength between the metal foil and the metal plate can be ensured. [Prior art documents] [Patent documents]
[0004] [Patent Document 1] JP 2011-129328 A Summary of the Invention [Problem to be solved by the invention]
[0005] In conventional batteries, the current collecting tabs are joined to the current collecting terminals separately, so there is a problem that power cannot be taken out from some electrodes if welding defects occur. This is particularly problematic when an electrode laminate is used for the power generating element. Therefore, there has been a demand for a battery with improved structural reliability to prevent such problems from occurring.
[0006] In view of the above circumstances, an object of the present disclosure is to provide a battery that can improve the structural reliability. [Means for solving the problem]
[0007] As one aspect for solving the above-mentioned problems, the present disclosure provides a battery comprising: a power generating element having a plurality of current collecting tabs lined up in the thickness direction; and a current collecting terminal joined to the current collecting tab, wherein at least one of the current collecting tabs has at least one slit dividing an end of the current collecting tab in the width direction, and each portion of the end of the current collecting tab divided across the slit is electrically connected to another current collecting tab adjacent to it in the thickness direction.
[0008] In the battery, the end portions of the current collecting tabs divided by the slit may be electrically connected to other current collecting tabs arranged at different positions in the thickness direction. Each current collecting tab may have at least one slit, and each end portion of the current collecting tab divided by the slit may be electrically connected to each end portion of the other current collecting tab adjacent in the thickness direction. Furthermore, the end portion of the current collecting tab and the end portion of the other current collecting tab may be electrically connected by being bent inward and contacting each other. Effect of the Invention
[0009] In the battery of the present disclosure, each portion of the current collecting tab divided by the slit is electrically connected to the other current collecting tab adjacent in the thickness direction. In this state, the current collecting tab is joined to the current collecting terminal. Therefore, even if a joint defect occurs in a part of the joint portion between these electrically connected current collecting tabs and the current collecting terminal, these current collecting tabs and the current collecting terminal are electrically connected via the other joint portion. In other words, power can be taken out from the power generating element without electrically isolating the power generating element having the current collecting tab with the welding defect. Therefore, the battery of the present disclosure can improve the structural reliability. [Brief description of the drawings]
[0010] [Figure 1] (A) is a perspective view of the battery 100. (B) is an exploded perspective view of the battery 100. [Diagram 2] FIG. 2 is a schematic diagram of a cross section taken along line II-II in FIG. 1(B). [Diagram 3] FIG. 11 is a perspective view of a negative electrode current collector tab 11b. [Figure 4] 4A is a front view observed from IVA in Fig. 3. (B) is a cross-sectional view taken along IVB-IVB in Fig. 3. (C) is a cross-sectional view taken along IVC-IVC in Fig. 3. [Diagram 5] 4(B) and 4(C), respectively, and are cross-sectional views showing a state where a negative electrode current collector tab 11b is joined to a negative electrode current collector terminal 20b. [Figure 6] 6A is a front view of another embodiment of the negative electrode current collector tab 11b, (B) is a cross-sectional view taken along line VIB-VIB in FIG. 6A, and (C) is a cross-sectional view taken along line VIC-VIC in FIG. 6A. [Figure 7] 7A is a front view of another embodiment of the negative electrode current collector tab 11b, (B) is a cross-sectional view taken along line VIIB-VIIB in FIG. 7A, and (C) is a cross-sectional view taken along line VIIC-VIIC in FIG. 7A. [Figure 8] 1A to 1C are schematic diagrams illustrating steps of a battery manufacturing method according to an embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0011] [battery] The battery of the present disclosure will be described with reference to one embodiment, a battery 100. Fig. 1(A) shows a perspective view of the battery 100, and Fig. 1(B) shows an exploded perspective view of the battery 100. Fig. 2 shows a schematic diagram of a cross section taken along line II-II in Fig. 1(B).
[0012] 1(A) and 1(B), the battery 100 includes a power generating element 10 having a plurality of current collecting tabs (negative electrode current collecting tab 11b and positive electrode current collecting tab 15b) arranged in the thickness direction, and current collecting terminals (negative electrode current collecting terminal 20a and positive electrode current collecting terminal 20b) joined to the current collecting tabs. In Figs. 1(A) and 1(B), the current collecting tabs are arranged on the same surface of the power generating element 10, but this is not limited thereto, and the current collecting tabs may be arranged on different surfaces of the power generating element 10. The same applies to the arrangement positions of the current collecting terminals.
[0013] <Power generation element 10> The power generating element 10 is a power generating component of a battery, and may be a laminate in which electrodes are stacked, or may be a wound body in which electrodes are wound. The type of the power generating element 10 is not particularly limited, and may be a power generating element for a liquid battery or a power generating element for an all-solid-state battery. The shape of the power generating element 10 is not particularly limited, and may be, for example, a rectangular shape in a plan view. FIG. 1 illustrates a battery 100 including a power generating element 10 that is a laminate in which electrodes for an all-solid-state battery are stacked. The power generating element 10 that is a laminate in which electrodes for an all-solid-state battery are stacked will be described below. However, the configuration of the power generating element 10 is not limited to this.
[0014] The power generating element 10 includes a negative electrode collector layer 11, a negative electrode active material layer 12, a solid electrolyte layer 13, a positive electrode active material layer 14, and a positive electrode collector layer 15 in this order in the thickness direction. The power generating element 10 may include a plurality of electrode bodies 16 in the thickness direction, with the negative electrode collector layer 11, the negative electrode active material layer 12, the solid electrolyte layer 13, the positive electrode active material layer 14, and the positive electrode collector layer 15 as one repeating unit (electrode body 16). The electrode bodies 16 may be stacked in series or in parallel. In addition, when the power generating element 10 includes a plurality of electrode bodies 16, adjacent electrode bodies 16 may share the positive electrode collector layer 11 or the negative electrode collector layer 15. FIG. 1 shows a power generating element 10 including a plurality of electrode bodies 16.
[0015] (Negative electrode current collector layer 11) The negative electrode current collector layer 11 is a sheet-shaped metal foil. The negative electrode current collector layer 11 includes a negative electrode flat plate portion 11a that contacts the negative electrode active material layer 12, and a negative electrode current collector tab 11b that extends outward from the negative electrode flat plate portion 11a. The negative electrode current collector tab 11b is a member for connecting the negative electrode flat plate portion 11a to the negative electrode current collector terminal 40a. The negative electrode flat plate portion 11a and the negative electrode current collector tab 11b may be made of a single member, or may be made of separate members. When the power generating element 10 has a plurality of electrode bodies 16, the negative electrode current collector tabs 11b may be arranged so as to be linearly aligned in the thickness direction.
[0016] The metal constituting the negative electrode current collector layer 11 is not particularly limited, and examples thereof include Cu, Ni, Cr, Au, Pt, Ag, Al, Fe, Ti, Zn, Co, stainless steel, and the like. Cu is preferable. The negative electrode current collector layer 11 may have some kind of coating layer (e.g., a carbon coating layer) on its surface to adjust the resistance. The thickness of the negative electrode current collector layer 11 may be, for example, 0.1 μm or more and 1 mm or less.
[0017] (Negative electrode active material layer 12) The negative electrode active material layer is a sheet-like layer containing a negative electrode active material. The type of the negative electrode active material is not particularly limited. For example, silicon and Si alloys, silicon oxide and other silicon-based active materials, graphite, hard carbon and other carbon-based active materials, lithium titanate and other various oxide-based active materials, metallic lithium and lithium alloys can be mentioned.
[0018] The negative electrode active material layer 12 may optionally contain a conductive assistant, a binder, and a solid electrolyte. The type of the conductive assistant is not particularly limited. Examples include carbon materials such as acetylene black and ketjen black, and metal materials such as nickel, aluminum, and stainless steel. The type of the binder is not particularly limited. Examples include butadiene rubber (BR), butylene rubber (IIR), acrylate butadiene rubber (ABR), and polyvinylidene fluoride (PVdF). The type of the solid electrolyte is not particularly limited. For example, it may be an organic polymer electrolyte or an inorganic solid electrolyte. Inorganic solid electrolytes are preferred. This is because inorganic solid electrolytes have higher ionic conductivity and superior heat resistance compared to organic polymer electrolytes. The inorganic solid electrolyte may be an oxide solid electrolyte or a sulfide solid electrolyte. A sulfide solid electrolyte is preferred. Examples of oxide solid electrolytes include lithium lanthanum zirconate, LiPON, Li 1+X Al X Ge 2-X Examples of the sulfide solid electrolyte include Li2S-P2S5, Li2S-SiS2, LiI-Li2S-SiS2, LiI-Si2S-P2S5, Li2S-P2S5-LiI-LiBr, LiI-Li2S-P2S5, LiI-Li2S-P2O5, LiI-Li3PO4-P2S5, Li2S-P2S5-GeS2, etc.
[0019] The content of each component in the negative electrode active material layer 12 may be appropriately set depending on the purpose. The thickness of the negative electrode active material layer may be, for example, 0.1 μm or more and 1 mm or less.
[0020] (Solid electrolyte layer 13) The solid electrolyte layer 13 is a sheet-like layer containing a solid electrolyte. The type of the solid electrolyte is not particularly limited, and can be appropriately selected from solid electrolytes that can be used for the negative electrode active material layer.
[0021] The solid electrolyte layer 13 may contain an arbitrary binder. The type of binder is not particularly limited, and can be appropriately selected from binders that can be used in the negative electrode active material layer.
[0022] The content of each component in the solid electrolyte layer 13 may be appropriately set depending on the purpose. The thickness of the solid electrolyte layer 13 may be, for example, 0.1 μm or more and 1 mm or less.
[0023] (Cathode active material layer 14) The positive electrode active material layer 14 is a sheet-like layer containing a positive electrode active material. The type of the positive electrode active material is not particularly limited. For example, various lithium-containing composite oxides such as lithium cobalt oxide, lithium nickel oxide, lithium manganese oxide, lithium nickel cobalt oxide, lithium nickel cobalt manganese oxide, and spinel-based lithium compounds can be used.
[0024] The positive electrode active material layer may optionally contain a conductive assistant, a binder, and a solid electrolyte. The types of the conductive assistant, binder, and solid electrolyte are not particularly limited, and can be appropriately selected from the conductive assistant, binder, and solid electrolyte that can be used in the negative electrode active material layer.
[0025] The content of each component in the positive electrode active material layer 14 may be appropriately set depending on the purpose. The surface of the positive electrode active material may be covered with an oxide layer such as a lithium niobate layer, a lithium titanate layer, or a lithium phosphate layer. The thickness of the positive electrode active material layer 14 may be, for example, 0.1 μm or more and 1 mm or less.
[0026] (Positive electrode current collector layer 15) The positive electrode current collector layer 15 is a sheet-shaped metal foil. The positive electrode current collector layer 15 includes a positive electrode flat plate portion 15a that contacts the positive electrode active material layer 14, and a positive electrode current collector tab 15b that extends outward from the positive electrode flat plate portion 15a. The positive electrode current collector tab 15b is a member for connecting the positive electrode flat plate portion 15a to the positive electrode current collector terminal 40b. The positive electrode flat plate portion 15a and the positive electrode current collector tab 15b may be made of a single member, or may be made of separate members. When the power generating element 10 has a plurality of electrode bodies 16, the positive electrode current collector tabs 15b may be arranged so as to be linearly aligned in the thickness direction.
[0027] The metal constituting the positive electrode collector layer 15 is not particularly limited, but examples thereof include Cu, Ni, Cr, Au, Pt, Ag, Al, Fe, Ti, Zn, Co, stainless steel, etc. Al is preferable. The positive electrode collector layer 15 may have some kind of coating layer (e.g., a carbon coating layer) on its surface to adjust the resistance. The thickness of the positive electrode collector layer 15 may be, for example, 0.1 μm or more and 1 mm or less.
[0028] (Current collecting tab shape) The battery 100 has a current collecting tab with a characteristic shape. The characteristic shape of the current collecting tab will be described below with a focus on the negative electrode current collecting tab 11b. However, the characteristic shape of the current collecting tab may also be applied to the positive electrode current collecting tab 15b. Therefore, the following description can also be applied to the positive electrode current collecting tab 15b.
[0029] Fig. 3 shows a perspective view of the negative electrode current collector tab 11b. Fig. 4(A) shows a front view observed from IVA in Fig. 3, Fig. 4(B) shows a cross-sectional view cut along IVB-IVB in Fig. 3, and Fig. 4(C) shows a cross-sectional view cut along IVC-IVC in Fig. 3. Figs. 5(A) and 5(B) show cross-sectional views corresponding to Figs. 4(B) and 4(C), respectively, when the negative electrode current collector tab 11b is joined to the negative electrode current collector terminal 20b. Here, in Fig. 3, the X direction is the extension direction (direction in which the current collector tab extends), the Y direction is the width direction (width direction of the current collector tab), and the Z direction is the thickness direction (thickness direction of the current collector tab), which are orthogonal to each other.
[0030] As shown in Figures 3 and 4(A) to (C), multiple negative electrode current collector tabs 11b are arranged side by side in the thickness direction. Each negative electrode current collector tab 11b has three slits 11c that divide the end (the outer end in the extension direction) of the negative electrode current collector tab 11b in the width direction. As a result, the end of each negative electrode current collector tab 11b is divided into four portions 11d.
[0031] Each portion 11d of the end of the negative electrode current collector tab 11b divided by the slit is electrically connected to a portion 11d of the end of another negative electrode current collector tab 11b adjacent in the thickness direction, which is divided by the slit 11c. At this time, the portion 11d of the end of the negative electrode current collector 11b divided across the slit 11c is electrically connected to the other negative electrode current collector tabs 11b arranged at different positions in the thickness direction. In addition, the portion 11d of one adjacent negative electrode current collector tab 11b and the portion 11d of the other negative electrode current collector tab 11b are connected by bending their ends (particularly the tip portions) inward.
[0032] In this way, the battery 100 has negative electrode current collector tabs 11b with each end 11d woven in, and each negative electrode current collector tab 11b is electrically connected to each other as shown by the arrows in Fig. 4(A). Then, as shown in Fig. 5(A)(B), each portion 11d of the negative electrode current collector tab 11b is joined to the negative electrode current collector terminal 20a. In Fig. 5(A)(B), the joined portion is indicated by B.
[0033] Since the battery 100 has the negative electrode current collector tabs 11b with such a characteristic shape, each negative electrode current collector tab 11b is electrically connected to the other negative electrode current collector terminal 20a. Even if a joint failure occurs in a part of the joint between the negative electrode current collector tab 11b and the negative electrode current collector terminal 20a, the negative electrode current collector tab 11b and the negative electrode current collector terminal 20a are electrically connected via the other joint. In other words, power can be taken out from each electrode body 16 without electrically isolating the electrode body 16 having the negative electrode current collector tab 11b with a welding failure. Therefore, the battery 100 can improve the structural reliability.
[0034] The shape of the slit 11c in the shape 1b of the negative electrode current collector tab 1 is not particularly limited, as long as it divides the end of the negative electrode current collector tab 11b. In FIG. 3, the slit 11c is a cut having a linear shape along the extension direction. The length of the slit 11c in the extension direction is not particularly limited, as long as each part 11d of the negative electrode current collector tab 11b divided by the slit 11c can be connected to another negative electrode current collector tab 11b. The length of each slit 11c may be the same or different. The number of slits 11c in the negative electrode current collector tab 11b is not particularly limited, and at least one slit 11c is sufficient. FIG. 3 shows a negative electrode current collector tab 11b having three slits 11c. The number of slits 11c in each negative electrode current collector tab 11b may be the same or different.
[0035] The method of electrically connecting the negative electrode current collector tabs 11b adjacent to each other in the thickness direction is not particularly limited. In FIG. 3, the portions 11d of the negative electrode current collector tabs 11b are electrically connected by direct contact, but may be electrically connected via a conductive member, for example. The number of the portions 11d of the negative electrode current collector tabs 11b to be electrically connected is not particularly limited. The portions 11d (particularly the tip portions) of three or more negative electrode current collector tabs 11b may be folded and electrically connected. FIG. 3 shows a form in which the portions 11d of two negative electrode current collector tabs 11b are folded and electrically connected. In addition, in FIG. 3, the respective portions 11d are folded inward and contacted with each other to be electrically connected, but the connection method is not limited to this. For example, each portion may simply be contacted without being folded. In addition, the direction in which the ends 11d are folded is not particularly limited, and may be one side or the other side in the thickness direction, or a form in which these are mixed. 3, there may be negative electrode current collector tabs 11b that are not connected to adjacent negative electrode current collector tabs 11b. In this case, the negative electrode current collector tabs 11b that are not connected to adjacent negative electrode current collector tabs 11b may also be bent to facilitate connection to the negative electrode current collector terminal 20a.
[0036] The method of joining the negative electrode current collector tab 11b and the negative electrode current collector terminal 20a is not particularly limited, and a known method can be appropriately adopted. For example, joining methods such as soldering, ultrasonic bonding, and laser welding can be used. In addition, in Fig. 5 (A) and (B), the ends 11d are joined at the overlapping portions, but this is not limited. The number of joining points is also not particularly limited, and may be at least one. This is because, as described above, each of the woven negative electrode current collector tabs 11b is electrically connected to each other.
[0037] Next, other forms of the negative electrode current collector tab 11b will be described. In FIG. 3, each negative electrode current collector tab 11b has a slit 11c, but the battery of the present disclosure is not limited to this, and at least one negative electrode current collector tab 11b may have a slit. For example, a form in which only the third negative electrode current collector tab 11b from the top has a slit 11c among five negative electrode current collector tabs 11b arranged in the thickness direction will be described. FIG. 6(A) shows a front view of this form, FIG. 6(B) shows a cross-sectional view taken along VIB-VIB in FIG. 6(A), and FIG. 6(C) shows a cross-sectional view taken along VIC-VIC in FIG. 6(A).
[0038] As shown in Figures 6(A) to 6(C), one portion 11d of the end of the negative electrode current collector tab 11b divided by the slit 11c is electrically connected to the other negative electrode current collector tab 11b adjacent to it on the upper side in the thickness direction, and the other portion 11d is electrically connected to the other negative electrode current collector tab 11b adjacent to it on the lower side in the thickness direction. In this way, each end 11d of the negative electrode current collector tab 11b having the slit 11c is woven into each adjacent negative electrode current collector tab 11b, and as shown by the arrows in Figure 6(A), the negative electrode current collector tab 11b having the slit 11c and each adjacent negative electrode current collector tab 11b are electrically connected to each other via each end 11d.
[0039] Therefore, even if a joint defect occurs in a part of the joint between these electrically connected negative electrode current collector tabs 11b (one set of negative electrode current collector tabs) and the negative electrode current collector terminal 20a, the one set of negative electrode current collector tabs 11b and the negative electrode current collector terminal 20a are electrically connected via the other joint parts. That is, in one set of negative electrode current collector tabs 11b, power can be taken out from all electrode bodies 16 without electrically isolating the electrode body having the negative electrode current collector tab 11b with the welding defect. Therefore, the battery 100 having such a configuration of the negative electrode current collector tabs 11b can improve the structural reliability.
[0040] Further, another embodiment of the negative electrode current collector tab 11b will be described. In FIG. 3, each portion 11d of the end of the negative electrode current collector tab 11b divided by the slit 11c is electrically connected to each portion 11d of the end of the other negative electrode current collector tab 11b arranged at different positions in the thickness direction, but the battery of the present disclosure is not limited to this, and each portion 11d may be electrically connected to the same other negative electrode current collector tab 11b. For example, a form in which the second and third negative electrode current collector tabs 11b from the top have the slit 11c in four negative electrode current collector tabs 11b arranged in the thickness direction will be described. FIG. 7(A) shows a front view of this embodiment, FIG. 7(B) shows a cross-sectional view taken along line VIIB-VIIB in FIG. 7(A), and FIG. 7(C) shows a cross-sectional view taken along line VIIC-VIIC in FIG. 7(A).
[0041] As shown in Figs. 7(A) to (C), each portion 11d of the end of the negative electrode current collector tab 11b divided by the slit 11c is electrically connected to each portion 11d of the end of the same other negative electrode current collector tab 11b. Therefore, even if a joint failure occurs in a part of the joint between these electrically connected negative electrode current collector tabs 11b (one set of negative electrode current collector tabs) and the negative electrode current collector terminal 20a, the set of negative electrode current collector tabs 11b and the negative electrode current collector terminal 20a are electrically connected via the other joint portion. That is, in one set of negative electrode current collector tabs 11b, power can be taken out from all the electrode bodies 16 without electrically isolating the electrode body having the negative electrode current collector tab 11b with the welding failure. Therefore, the battery 100 having such a configuration of the negative electrode current collector tabs 11b can improve the structural reliability. <Collector terminal> The current collector terminals are members for connecting the power generating element 10 to an external member. The negative current collector terminal 40a is connected to the negative current collector tab 11b, and the positive current collector terminal 40b is connected to the positive current collector tab 15b. The material of the terminals is not particularly limited, and can be appropriately selected from metal materials that can be used for the negative current collector terminal 40a or the positive current collector terminal 40b.
[0042] <Other materials> The battery 100 may be housed in an exterior body. The type of the exterior body is not particularly limited, and examples thereof include a metal housing such as a metal laminate, e.g., an Al laminate, or a metal can.
[0043] [Battery manufacturing method] Next, a method for manufacturing a battery according to the present disclosure will be described. The method for manufacturing a battery according to the present disclosure is not particularly limited, and the battery can be manufactured by a known method. Hereinafter, one embodiment of a method for manufacturing a battery including a power generating element that is a laminate in which electrodes for an all-solid-state battery are laminated will be described.
[0044] The manufacturing method of the battery according to the embodiment includes an electrode preparation step S1, a slit providing step S2, an electrode lamination step S3, a current collecting tab weaving step S4, and a current collecting terminal joining step S5. A schematic diagram showing each step is shown in FIG.
[0045] <Electrode preparation process S1> The electrode preparation step S1 is a step of preparing a negative electrode and a positive electrode. The negative electrode and the positive electrode can be prepared by a known method. For example, the material constituting the negative electrode active material layer is dispersed in an organic solvent, and the obtained slurry is applied to the negative electrode current collector layer and dried to obtain a negative electrode. A positive electrode can be obtained by using a similar method.
[0046] The solid electrolyte layer may be prepared by laminating it on either the negative electrode or the positive electrode, or may be prepared separately from these electrodes. For example, the material constituting the solid electrolyte layer may be dispersed in an organic solvent, applied to the surface of the negative electrode active material layer of the negative electrode, and dried to laminate the solid electrolyte layer on the negative electrode. Alternatively, a solid electrolyte layer may be prepared separately and disposed between the positive electrode and the negative electrode in the electrode lamination step S3.
[0047] Here, the negative electrode and the positive electrode used inside the laminate may have electrode layers formed on both sides.
[0048] <Slit providing step S2> The slit providing step S2 is a step of providing slits to each current collecting tab. A known method can be appropriately applied as the slit providing method. For example, it is sufficient to simply cut the current collecting tab so as to have the slits.
[0049] <Electrode lamination process S3> The electrode lamination step S3 is a step of laminating the negative electrode and the positive electrode to prepare a laminate. The method of laminating each electrode is not particularly limited, and a known method can be appropriately adopted. After preparing the laminate, the laminate may be pressurized to strengthen the adhesion of each electrode.
[0050] <Weaving process S4> The weaving step S4 is a step of weaving the end portions of each current collecting tab divided by the slits. The weaving step S4 may be performed in parallel with the electrode stacking step S3. That is, the weaving of each current collecting tab may be performed while stacking the negative and positive electrodes.
[0051] <Collector terminal joining process S5> The current collecting terminal joining step S5 is a step of joining each of the woven current collecting tabs to each of the current collecting terminals. The joining method is not particularly limited, and examples thereof include laser welding, ultrasonic joining, and soldering. [Explanation of symbols]
[0052] 10 Power generation elements 11 Negative electrode current collector layer 11a Negative electrode flat plate part 11b Negative electrode current collecting tab 11c Slit 11d part 12 Negative electrode active material layer 13 Solid electrolyte layer 14 Cathode active material layer 15 Positive electrode current collector layer 15a Positive electrode flat plate part 15b Positive electrode current collecting tab 16 Electrode body 20a Negative current collector terminal 20b Positive current collecting terminal 100 batteries
Claims
1. A power generating element including a plurality of current collecting tabs arranged in a thickness direction; a current collecting terminal joined to the current collecting tab, Each of the current collecting tabs has at least one slit dividing an end of the current collecting tab in a width direction, each end portion of the current collecting tab divided across the slit is electrically connected to each end portion of another current collecting tab adjacent thereto in the thickness direction; the portion of the end of the current collecting tab and the portion of the end of the other current collecting tab are electrically connected to each other by being bent inward and contacting each other; battery.
2. The battery according to claim 1 , wherein the end portions of the current collecting tab divided by the slit are electrically connected to other current collecting tabs arranged at different positions in the thickness direction.
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